Sequencing of the human genome and other recent developments in human genomics has revealed that the genomic makeup between any two humans has over 99.9% similarity. The relatively small number of variations in DNA between individuals gives rise to differences in phenotypic traits, and is related to many human diseases, susceptibility to various diseases, and response to treatment of disease. Variations in DNA between individuals occur in both coding and non-coding regions, and include changes in bases at a particular locus in genomic DNA sequences, as well as insertions and deletions of DNA. Changes that occur at single base positions in the genome are referred to as single nucleotide polymorphisms, or “SNPs.”
While SNPs are relatively rare in the human genome, they account for a majority of DNA sequence variations between individuals, occurring approximately once every 1,200 base pairs in the human genome (see International HapMap Project, www.hapmap.org). As more human genetic information becomes available, the complexity of SNPs is beginning to be understood. In turn, the occurrences of SNPs in the genome are becoming correlated to the presence of and/or susceptibility to various diseases and conditions.
As these correlations and other advances in human genetics are being made, medicine and personal health in general are moving toward a customized approach in which a patient will make appropriate medical and other choices in consideration of his or her genomic information, among other factors. Thus, there is a need to provide individuals and their caregivers with information specific to the individual's personal genome toward providing personalized medical and other decisions.